# What is the slope of a line perpendicular to the x-axis?

##### 2 Answers

#### Answer:

undefined

#### Explanation:

the slope of a line parallel to the

the slope of a line perpendicular to another will have a slope which is its negative reciprocal.

the negative reciprocal of a number is

the negative reciprocal of

this is undefined, since one cannot define the value of any number that is divided by

#### Answer:

We say vertical lines have "no slope," horizontal lines have zero slope. The equation is

#### Explanation:

One may use a direction vector,